space

At the bowling alley tonight, after discussing the stock market for a while, my friend says to me, “Did you hear about the asteroid that’s supposed to hit us tomorrow?” I thought he was kidding. So I whipped out my shiny iPhone and checked to see what Google could tell me about this. To my surprise, it told me quite a bit. According to this story from the National Geographic Society,

A boulder-size asteroid discovered just a few hours ago will become a bright fireball when it enters Earth’s atmosphere at about 10:46 eastern time tonight, astronomers announced.

Holy carp! I added the boldface over the really important bits. Let’s read it together, shall we? A boulder-size asteroid, discovered just a few hours ago… That’s really unsettling. I thought we had satellites whose sole purpose was to watch for these things. Oh well, at least it’s a small one that will most likely burn up in the atmosphere. The article did go on to say

“If the object was ten times the size [as the one detected today], we would have picked it up several days in advance,” Spahr said.

“Then we could say, OK, you guys in Africa, pick up and move 50 miles [80 kilometers].”

I was watching the press conference on NASA TV tonight discussing the latest delay on STS-122 that was supposed to have launched yesterday, but now looks like it will launch on Sunday. During the questions from reporters, one asked how many delays could they endure before it impacted the next mission. One of the men on the panel said that basically they had plenty of time before the Feb 14 launch of the next mission. But he also said, “Of course, you can’t launch the next one until this one gets back” (paraphrase). Really? Can NASA only track one spacecraft at a time, or are they just being cautious?

I really wish our space program were father along than it is. We just seem to keep doing the same things, and not really expanding the program. It’s very frustrating. If they really can’t track more than one craft at a time, then it seems like doing anything more than poking along like we are now, running a delivery service for the space station, is all our space program is going to be for a while.

First, light travels through a vacuum at 186,282.397 miles per second. That works out to 670,616,629.2 miles per hour, which is 16,094,799,100.8 miles per day, which is 5,878,625,371,567.2 miles per year. That’s 5.8 trillion miles in a year. That’s really fast.

Now, the book went on to say that besides our sun, the nearest star to us is Alpha Centauri at a distance of 4.37 light-years. That works out to 25,689,592,873,748.7 miles from Earth. So, our “nearest” star is roughly 25 trillion miles away from us.

Feeling small? No? OK, try this. Our solar system is located in one arm of our galaxy. The center of our galaxy, according to the book, is about 30,000 light-years away from us. That means that we are about 176,358,761,147,010,000 miles away from the center of the Milky Way. That’s 176 quadrillion miles away.

Still comprehending the numbers? The latest issue of Astronomy Magazine has an article about a collision of 4 galaxies that has been spotted that is 5 billion light-years away. That works out to 29,393,126,857,835,000,000,000 miles away. That’s 29 sextillion miles away.

On Sunday I was watching a program about a manned mission to Mars, and it got me thinking about these huge distances again and how long it would take to traverse them in a spacecraft. From what I can tell, the fastest manned spacecraft so far has moved at around 27,000 miles per hour. I found an article from 2006 about a prototype that was purported to travel at 36,000 mph. But let’s use the 27,000 mph figure. At that speed, assuming it stays constant, the craft could travel 236,682,000 miles in a year. At that speed, to go just one light-year would take 24,837 years. To get to the places I mentioned earlier would take

Alpha Centauri: 108,540 years

Milky Way center: 745,129,588 years

Galaxy collision: 124,188,264,666,666 years

And some humans think we are alone in this vast, great expanse of space.

Note: The numbers I used for the speed of light and the distance to Alpha Centauri are different from what is in the book. I found more accurate values for these on WikiPedia, so I used those. It only changes the calculations by a few billion miles… Also, please note that I’m no mathematician, and some of these calculations may not be completely accurate. I did the best I could.